Aniston and Cox each shared a selection of photos from their time working together on the hit US sitcom, as well as hanging out in real life.

Kudrow, who studied biology at university before achieving worldwide fame in Friends, played loveable and eccentric Phoebe Buffay.

She's gone on to have success in films, including cult classic Romy And Michele's High School Reunion, and further TV shows including The Comeback, Space Force and Feel Good.

Aniston, 54, who played Rachel Green in Friends, wrote: "Please join me in celebrating one of my favourite people on the planet. LISA KUDROW!!

"She's been my friend and my family for nearly 30 incredible years. I cherish you... I love you, my sweet Floosh.

"One of the most talented comedians/actors I've had the great honour to work with for all these glorious years and more to come! Happy Lisa's Birthday!"

One of the pictures Aniston shared was from their 1996 Milk magazine advertisement, with the pair sporting milk moustaches.

Kudrow replied: "My Joooiest Joooo I love you beyond my dear friend forever!"

Cox, 59, who played neurotic but loveable Monica Geller in Friends, said: "Happy Birthday my Loot. This is my second attempt: ChatGPT didn't give you nearly the amount of love I feel for you.

"You are the smartest, funniest, most thoughtful person. I always feel seen and loved when I'm around you. That's the gift you give to those you love."

Kudrow replied: "Oh Cahoot. I love you so much and guess what? I always feel seen by you."

Kudrow shared an Instagram Story of her blowing out candles on a cake, with a large bunch of flowers in the front of the shot, with the message: "Thanks for all the happy birthday wishes. This wish is for all of you!"

US actors David Schwimmer, Matt LeBlanc and Matthew Perry also starred in the hit show.

In 2021, a much-hyped reunion special marked the first time the cast had been together on screen for 17 years.

Friends, which focused on a group of six 20-somethings living in New York, was first broadast on 22 September, 1994, staying on our screens for 10 seasons, with the final episode airing on 6 May 2004.

A pop culture phenomenon, and one of the most successful TV shows of all time, it's said that you are never more than 20 minutes away from a re-run somewhere in the world.